Neonatal herpes can occur when the neonate is exposed to herpes simplex virus in the maternal genital tract during labour. Attack rates are highest when the mother has a newly acquired infection and, therefore, does not have antibodies to protect the neonate. Even with early therapy, there is significant morbidity and mortality associated with neonatal herpes, suggesting that preventing neonatal herpes simplex virus exposure or early recognition of exposure is important. The incidence of neonatal herpes has not declined despite national guidelines for prevention. This suggests that the prevention guidelines need to be re-addressed.Keywords Herpes, neonate, prevention.Please cite this paper as: Gardella C, Brown Z. Prevention of neonatal herpes. BJOG 2011;118:187-192.
Epidemiology of genital herpesBased on serological data from a large National Health and Nutrition Examination Survey (NHANES), 22% of pregnant women in the USA are infected with herpes simplex virus 2 (HSV-2), 63% are HSV-1 seropositive, 13% have both HSV-1 and HSV-2, and 28% are seronegative. 1 In the general population, for the first time since the 1976 inception of NHANES, the seroprevalence of HSV-2 has decreased; overall, the age-adjusted HSV-2 seroprevalence was 17% in 1999-2004, compared with 21% in 1988-94, a relative decrease of 19% between the two study periods. Among those infected with HSV-2, the percentage who reported being diagnosed was 14.3% in 1999-2004 and 9.9% in 1988-94, suggesting that more providers are aware of genital herpes, and able to make appropriate diagnoses. 2 However, the vast majority of people infected with HSV-2 remain undiagnosed and, therefore, untreated and able to spread the infection. Between 75% and 90% of HSV-2-infected people are not aware of having the infection. [3][4][5][6] This is important because most sexual transmission of HSV occurs during episodes of subclinical reactivation among persons with unrecognized infection. 4,7-10 Virtually all HSV-2 seropositive people have intermittent shedding from the genital mucosa, and most have mild (and hence unrecognized and undiagnosed) disease. 5 In the absence of symptoms, HSV-2 can be detected in the genital tract, by viral culture, on 3% of days for the first year after initial infection, then on 1% of days for the next 2 years. HSV-2 DNA can be detected by polymerase chain reaction testing 15-20% of days. 11,12 Recent data suggest that HSV reactivation may occur much more frequently than previously understood, and may be characterised by frequent short bursts of viral shedding that do not correlate with symptoms. 13 As HSV-2 seroprevalence decreased, HSV-1 seroprevalence in the USA increased to 62% in 1988-94 from 57.7% in 1999-2004. 2 Among persons infected with HSV-1 but not HSV-2, a higher percentage reported a diagnosis of genital herpes in 1999-2004 compared with 1988-94 (1.8% versus 0.4%). 2 HSV-1 has emerged as a major cause of genital herpes among college-age populations, in which up to 80% of new cases of genital HSV were caused by HSV-1. [14][1...